Book-holder



(No Model.)

J. W. HANSON & J. L. H. BARR.

BOOK HOLDER.

No. 337,435. Patented Mar. 9 1886.

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JOSEPH W. RANSON AND JAMES L. H. BARR, OF BAIAVIA, OHIO.

BOOK-HOLDER.

SPECIFICATION forming part of Letters Patent No. 337,435, dated March 9, 1886.

Application filed July 2, 1885.

To all whom it may concern:

Be it known that we, JOSEPH \V. HANSON and JAMES L. H. BARR, citizens of the United States, residing at Batavia, in the county of Olermont and State of Ohio, have invented a new and useful Improvement in Book- Holders, of which the following is a specifithe book lies in such a manner that when one side is raised the other is depressed in like proportion. These objects are accomplished by the following mechanism,in which- Figure 1 is a front View with part of the desk cut away, showinggeneral arrangement of mechanism with book in position. Fig. 2 is an isometric perspective view of mechanism detached from desk. Fig. 3 is a top View showing aperture in top ofdesk to receive the book, together with part of the mechanism.

Similar letters refer to like parts throughout the several views.

The mechanism is here shown in its simplest form as attached to a level-topped table or desk. It can, however, be attached as well to a desk or table having a slanting lid or top.

In Fig. 1, A is the book in position, the lids resting upon the two platforms B B. These platforms, on the under side and near each end, have T-shaped pieces a firmly attached, which project downward and are hinged to the ends of levers O O by means of pins 1), passing laterally through them and the forked ends of the levers, as shown.

Through the levers O G, and firmly attached thereto, is the shaft N. This shaft is provided with suitable bearings at each end, and acts as the center upon which the levers G O vibrate.

Firmly attached to the end of the shaft N is asegment of worm cog-gearing, D, into the Serial No. 170,542. (No model.)

screw or worm S. This screw revolves onjournals shown at each end of the threaded part, which have bearings in blocks securely attached to the front rail of the table. (Not shown.) These blocks bear against the shoulder formed at each end of the threaded part of the screw and prevent the screw from having any longitudinal movement while being rotated or at rest. The lower part of the screw is madelong enough to project below the side rails of the desk, sufficientto receive the knob K, so placed to the right of the center of the length of the desk as to be within easy reach of the hand, and at the same time not interfere with the knees of the person writing.

The platforms B B are held in position, at ways parallel with the top of the desk,by the following means: The T-shaped pieces a, which are hinged to the ends of the levers G O, and to the tops of which the platforms B B are attached, project downward below the ends of levers O O, and arehinged to the ends of the pieces 25 t by means of pins or rivets, as shown at a. The piecest t have holesg g at the center of their length. Through these holes are screws, which loosely attach the pieces to the frame of the desk, as shown. The manner in which this operates will be shown hereinafter.

It is obvious that if the knob K is rotated by the hand the threads of the screw S engaging in the teeth of the segment cog-gear D will cause the shaft N to rotate on its bearings with a greater or less degree of motion,in proportion to the amount the knob is turned. The levers C- 0, being firmly attached to the shaft, are made to vibrate perpendicularly, and, being attached to the platforms B B at their ends, will cause one of them to ascend while the other descends. The pieces t it being of the same length as levers c 0-, and hinged at the same distance from the center, and being attached at the ends to the ends of the T-shaped pieces, as shown and described, it is obvious that with any amount of motion, up or down, of the platforms necessary for the purpose described, this combination of parts will hold the pages of the hook always level with the top of the operated by and in combination with the table, in accordance with the principles upon worm-gear D S, for the purpose described. which this Well-known mechanical movement JOSEPH- Vv HANSON opemtes.

5 I claim- The platforms B B and levers C C, the T- Vitnesses: shaped pieces a, attached to the under side of G. L. HINEs, the platforms, the pieces if t, and the shaft N, O. T. HINEs.

JAMES L. H. BARR. 

